Three new polls seem to be responsible for the change:
On this occasion, Gallup has made its racial breakdown available: Romney leads Obama 61%-39 among non-Hispanic whites.
This is about Romney's best white share result yet, comparing with the 60% white share that Congressional Republicans got in 2010 and well ahead of McCain's 56% in 2010. (More white share comparisons here—scroll down). And it results in one of Romney's largest recorded overall leads.
Rasmussen's Premium Platinum subscribers learn that Romney's white share has dropped a point, to 57%.
Typical of the MSM, IBD/TIPP attributes Romney's weakening to losses among independents and (less typically) men and self-identified "conservatives." But in fact IBD/TIPP shows Romney's white share sharply down, at 53%, compared to 58% on October 10, when Romney led overall by 5 points.
Fox News Latino speculates Presidential Debate: In Round Two, Will Immigration and Latin America Come Up? (by Elizabeth Llorente, Oct. 16 2012). This would be a shrewd move by Obama, since Romney has shown every sign of wanting to pander on this issue, which would in turn alienate his only real hope: conservative white patriots.